Electromechanical door-releasing means



Nov. 24 1925.

. E. LEDBETTER ELECTfiOMECHANICP-L DOOR RELEASING mums Filed April 4, 1925 2 Sheets-Sheet 1 INVENTOR ATTORNEY Nov. 24 1925. 1,563,198

' E. LEDBETT ER ELBCTROMECHANIOAL DOOR RELEASING MEANS Filed April 4. 1925 2 Sheets-Sheet 2 Q bx Q 3% H2 .11... v.

WITNES Patented Nov. 2.4, 1 925.

ERNEST LEDBETTER, OF ST. LOUIS, MISSOURI.

ELECTROMECHANICAL DDOR-RELEASING MEANS.

Application filed April 4, 1925. Serial No. 20,876.

T (IN whom it; vii/(6y concern.

Be it known that 1, Farmer Lnnnn'rrnn, a citizen of the United States, residing at St. Louis, in the State of Missouri, have invented new and useful Improvements in Electromechanical Door-Releasing Means, of which the following is a specification.

The object of my said invention is the provision of peculiar and advantageous electromechanical means through the medium of which a person on an upper floor of a building is enabled when apprised of the identity of another person at the street door of the building to release the street door so that such other person may enter, thus obviating the necessity of the person on the upper floor descending to the street floor for the pur pose of admitting the second-named person.

Other objects and practical advantages will be understood from the following description and claims when the same are read in connection with the drawings, accompanying and forming part of this specification, in which Figure 1 is a side elevation illustrating a portion of the mechanism constituting the preferred embodiment of my invention.

Figure 2 is a horizontal section of the same.

Figure 3 is a view showing the switch and signal lights designed to be located on the upper floor of abuilding.

Figures 4 and 5 are views of details herein after explicitly referred to.

Figure 6 is a diagrammatic view illustrative of the electric connection.

Similar numerals of reference designate corresponding parts in all of the views of the drawings.

I show in Figures 1, 2 and 6 an electric motor 1, the armature shaft of which is equipped with a pulley 2, connected through a belt 3 with a larger pulley 4;, the said pulley 4 being fixed to a smaller pulley 5 which is connected through a belt 6 with a disk 7 adapted to be rotated and provided with a cam 8. All of this mechanism is enclosed by preference in a casing 9 which is carried by a street door 10, and which preferably has a pane of glass 11, so that the working of the mechanism may be observed by a person at the inner side of the said street door 10. The door 10 referred to is provided with a rectilinearly movable latch 12 for securing it in closed position, the said latch bolt 12 being connected in the ordinary well known manner with a rotary shank 13 at the inner side of the door, and the said shank 13 being equipped with an arm 14tto which is connected :1. bar 15 movable through the forward wall of the casing 9. At its rear end the bar 15 is provided with a headed re duced portion 16 which extends through an aperture at the forward end of a slidable bar 17 disposed in guides within the easing 9. A coiled spring 18 surrounds the bar portion 16 and is interposed between the forward end of the slidable bar 17 and an abutment 19 on the bar 15. Manifestly when the bar 17 is moved toward the left in Figure 1 the bar 15 and the latch bolt 12 will be retracted and the door 10 released for the opening of said door 10; and it will also be noticed that the bar 15 may be moved toward the left in Fi 'ure 1 without movement of the bar 17, this in order to permit of the latch bolt 12 being retracted by a person at the inner side of the door as when such person desires to leave a building.

In addition to the elements enumerated my improvement comprises a bell crank 20 engaged with and designed to be controlled by the cam 8, and connected at 20 with the bar 17. The said bell crank 20 is located in the casing 9 as are also terminals 21 and 22. Back of the rotary disk 7 are stationary terminals 23 and 24:, designed to be engaged by a. conductive shoe 25 on the disk 7 which conductive shoe is electrically connected with the terminal 21. At 29 are terminals shown in Figures 1 and 6 and designed to be bridged to but insulated from the lower arm of the bell crank 20. A conductive plate 22 is carried by but insulated from the upper arm of the bell crank 20 and is de' signed in one position to electrically connect the terminals 22.

In the preferred embodiment of my invention the arm 14 before alluded to is fixed on the shank '13 by a clip 30, Figures 2 and 5. It will also be noted that the said shank 13 is provided with the usual handle or knob 10, Figure 2.

In accordance with my invention an electric switch is arranged near the upper floor of a building and adjacent to a speaking tube which extends from such upper floor to a point outside of and adjacent to the door 10, and is designed to enable a person seeking entrance to state his name and and I also illustrate business to a person on the upper door. The lower portion oi? the spool-ring tube '60 is shown in Figure 4:, and is preteral'ily arranged adjacent to a push button 61 in connection with an electric hell (not shown). Also arranged adjacent to th switch ctand the upper end ot tie speali tube (30 are incandescent electric lamp-s i0 an 80, the said lamps being arr: ed adiace to propriate legends and being -.,.csig'ned to indicate when the door is unlatched and when the door is latched, respectively.

I illustrate in Figure 6 a t r iiinal 90 carried by the frame or casing of the door 10, a terminal 91 which contacts with the terminal 90 when the door is closed and is separated from the termi al 90 when the door is opened.

The electrical connections are pre such as shown in Figure 6, he source tric energy being designated by i. be understood, however, that any eti propriate electrical connections may be ployed without departure from the scope of my cl aimed invention.

In the practical operation oi" in improved mechanism when a person at the door presses against the push button 81, Figurel. or otherwise rings an alarm bell on an upper floor oi the building. the occupant of the upper floor calls through the spot, up; tube and then ii such occupant desires to permit the entrance of the party at the street door he or she closes the switch This puts in motion the electric motor 1 and brings about turning of the disk 7 in the direction indicated by arrow in Figure 1. hen this is done the bar 17 and the latch 12 will be retracted for the release oi the door, and it will be understood that the latch 12 will be maintained in retracted position incident to the turning of the disk? through a complete revolution, and at the end of such revolution the parts will. be restored to the illustrated positions and the door will be again latched. This is advantageous be cause it makes necessary momentary closure of the switch 50 and also because it makes it incumbent on the person at the street door to promptly enter upon actuation of the mechanism. When the disk 7 is turned in the direction indicated it will be noted that the lamp will be lighted and that the terminal 21 will bridge and elec trically connect the terminals 29, and it will also be noted that the conductive plate 22 on the bell crank 20 will be moved away "from the terminals 22 thereby breaking the circuit at that point. It will further be noted that. incident to the turning oi the disk 7 the conductive member 25 thereon will electrically connect the arcuate terminals 23 and 24 so that current will pass between said terminals and through the same. When after a revolution of the disk 7 the memes parts resume the positions shown in Figure 1 it will be noted that the electrical connections between the tern'iinal 21 and the terurin 29 and between the conductive memand the terminals 23 and will be ii'iterrupted while the electric connection beween the terminals 22 will be reed'ablished. ichanism l2 and lid bolt 12 in a retracted state 1. 7' trically reseat itself a another operation. rlanitestly when th' t minal 91 is in contact with the te n" the filament ot the lamp wi to glow to indicate that the door the circuit tor that purpose bein plus pole ol? the source of one it 7 the electric connection be tween the terminals 22 will be interrupted and electric connection will be established between the terminals 29 and also between the terminals 24 and 28 by the means and for the purpose described. On the initial n'iovement of the disk 7 in the direction indicated by arrow the connection between the terminals 22 will be interrupted and electrical connection will afterward be established between the terminals 29, and thereafter electric connection will be established between the terminals and 2d, the latter connection being maintained during a considerable portion of the revolution of the dislzi, and it being noticed in this con nection that the sole province of the ele ment 21 is to electrically connect the terminals 29, and that said element 21 has no electric connection with the conductive member 25.

I have specifically described the preferred embodiment of my invention in order to impart a exactunderstanding): of said embodiment. I do not desire. however, to be understood as confining myself to the specific construction and relative arrangement of parts, the scope of my invention being defined by my appended claims within which changes may be made without departure from my invention.

Having: described my invention, what I claim and desire to secure by Letters-Patent, is:

1. Electromechanical door releasing means comprising a latch bolt complementary to a door, a bar connected with and adapted on movement thereof in one direction to re-' tract said bolt, and a rotor, a cam movable therewith and a bell crank for retracting said bar, said rotor being operable by an electric motor, and said motor being aranged in a normally interrupted circuit with a source of electric energy and switch means, and means being provided on the rotor and on the bell crank for interrupting and reestablishing the electric circuit.

2. Electromechanical door releasing means comprising a latch bolt complementary to a door, a bar connected with and adapted on movement thereof in one direction to retract said bolt, and a rotor, a cam movable therewith and abell crank for retracting said bar, said rotor being operable by an electric motor, and said motor being arranged in a normally interrupted circuit with a source of electric energy and switch means, and means being provided on the rotor and on the bell crank for interrupting and reestablishing the electric circuit; the said latch bolt being combined and movable with a supplemental rectilinearly movable bar, and the said bar being provided with a reduced and headed portion movable in one direction independently of the first-named bar, and a coiled spring surrounding said reduced portion and interposed between opposed portions of said bars.

3. In electromechanical door releasing means, the combination of a latch bolt carried by and movable in a door, a bar connected with and adapted when moved in one direction to retract said bolt, a disk or rotor, an electric motor arranged in a normally open circuit with a source of electric energy and circuit making and breaking means and connected with and adapted to turn said disk or rotor, a bell crank connected with said bar and equipped with circuit closing means, a cam carried by the disk or rotor and connected with and adapted to actuate said bell crank, a conductive member carried by the disk or rotor, stationary spaced terminals for cooperation with said conductive member, terminals for cooperation with one of the circuit closing means of the bell crank and terminals adapted for cooperation with the other circuit closing means of the bell crank; the said terminals and circuit closing means being electrically connected with the source of electric energy and the motor and switch means substantially as described.

In testimony whereof I aflix my signature.

ERNEST LEDBETTER. 

